When it comes to drug abuse, underage drinking and smoking, recent years have seen the arrival of much-needed media campaigns and school programs designed to let kids know flat out: Do not engage. Of course, we still have much to do to curb the use of illicit drugs, but at least most adults are committed to telling kids the behavior is unacceptable.

So why should this rule not apply when it comes to teen sex?

Suddenly, the adults who were so quick, so adamant about condemning drugs, drinking and smoking begin to stammer and look at the floor. Sure, it's not good for teens to be having sex, these adults will allow, but c'mon -- they're going to do it anyway. So, they say, let's tell the kids not to do it. But let's also give them some condoms and other birth-control devices and tell them how to use them. You know, just in case.

To be consistent, then, we should also give kids clean syringes, low-tar cigarettes and tips on avoiding hangovers. But we don't, do we? And why? Because we know perfectly well that it would undermine our message that the behavior in question is unsafe -- no ifs, ands or buts. Why should it be any different when it comes to teen sex?

The fact is, it shouldn't be. That's why President Bush deserves so much credit for promoting an unambiguous abstinence-only message in sex education. It's important to say what we mean and mean what we say -- and that's what abstinence-only sex ed does. It tells our children, just as emphatically as we do with drugs, drinking and smoking, that we're taking a zero-tolerance, no-nonsense approach. Why? Because we love them, we want what's best for them and because it's the right thing to do.

This year, the federal government is spending about $167 million to teach kids the abstinence-only approach. "Abstinence-until-marriage is much more than 'just say no'," the Web site of the Abstinence Clearinghouse notes. "It is reality-relationship education. Abstinence-until-marriage education teaches the elements and skills needed in a healthy marriage."

A noble goal, indeed. But it's one that will prove quite an uphill climb for many parents, especially when you consider the fact that the federal government spends about 12 times as much on "comprehensive" sex ed (sometimes dubbed "abstinence-plus" to fool unsuspecting parents) as it does on abstinence-only sex ed.

One exceptionally effective element found in many abstinence-only approaches is the "virginity pledge." Critics have long disparaged them as useless, claiming that they are taken by the kids who are already more likely than their peers to abstain from sex. But a recent junk-science study that got a lot of media play went one step further, suggesting that virginity pledges could even be dangerous.

According to an article by professors Peter Bearman and Hannah Bruckner in the April 2005 issue of the Journal of Adolescent Health, young people who take virginity pledges have the same sexually transmitted disease (STD) rates as non-pledgers. Further, they strongly suggest that virginity pledgers are more likely to engage in other forms of sex.

Sounds bad -- until you learn that the Bearman and Bruckner study is seriously flawed. The problem, uncovered by Heritage Foundation researchers Robert Rector and Kirk Johnson, is that it focused on small subsets of data within the National Longitudinal Study of Adolescent Health. The suggestion that pledgers are more likely to engage in anal sex is based on a tiny subset of pledgers, amounting to 21 persons out of a total sample of 14,116. This "risky group" represents less than 1 percent of pledgers. When you look at pledgers as a whole, they are substantially less likely to engage in any form of sex (vaginal, anal or oral).

"They have described a subset in detail and implied that it reflects the group as a whole," Rector said. "This is like finding a small island in the middle of a vast ocean, describing only it and not the surrounding water, and then using that description to make people think the ocean is dry and rocky."

Kudos to these two Heritage heroes -- Robert Rector and Kirk Johnson -- for, once again, producing the sterling research that The Heritage Foundation is acclaimed for. As a mom, a family advocate and a colleague, I'm so very thankful for their work on behalf of America's kids and the truth. Just maybe, with great folks like Rector and Johnson continuing to boldly debunk the siren song of the "safe sex" crowd, adults will one day teach America's children the virtues of virtue.

Rebecca Hagelin is Vice President of Communications and Marketing at the Heritage Foundation